From the past, it is known that noise is radiated when signals flow through a cable connected to a board of an electronic apparatus. Thus, as countermeasures against so-called electromagnetic interference (EMI) for suppressing the noise, a method of attaching a core to a cable by, for example, inserting a cable into a tubular core or winding a cable around a bobbin-shaped core has been known.
Moreover, as disclosed in Japanese Unexamined Patent Publication No. H10-144407 and Japanese Unexamined Patent Publication No. 2005-123266, for example, a technique of integrating a core and a cable connector with a cable interposed to reduce the attachment space of the core in an electronic apparatus.
The frequency of radiated noise is different depending on the frequency of signals flowing through a cable. Thus, when the conventional technique is employed, it is necessary to adjust the frequency of noise to be suppressed by the core in advance by changing the type of the core attached to a cable or changing the number of turns of the cable wound around the cable depending on the specification of signals flowing through the cable. However, due to the influence of noise propagating from peripheral devices connected to an electronic apparatus after shipment, the frequency of noise radiated from the cable may be different from the frequency assumed in advance. In this case, it is necessary to re-adjust the frequency of noise to be suppressed by the core.
According to the technique disclosed in Japanese Unexamined Patent Publication No. H10-144407 and Japanese Unexamined Patent Publication No. 2005-123266, when the need to re-adjust the frequency of noise to be suppressed by the core occurs, it is necessary to change the type of the core by disassembling the cable connector because the core is included in the cable connector. Alternatively, it is necessary to replace the cable itself with a cable having a cable connector in which a different type of core is included. Moreover, since it is difficult to change the length of the cable which has been included in the product, it is difficult to perform the re-adjustment by changing the number of turns of the cable wound around the core.
An object of the present invention is to provide a relay connector capable of re-easily adjusting the frequency of noise to be suppressed.